Adjustable gearing device



Match 31, 1953 w. B. WATSON ETAL ADJUSTABLE GEARING DEVICE Filed Feb.14', 1951 m H: i'll II III I L f 'lHl IIIIH l x I C L i I i i :"TI 6 zajzed 2 6 1 4 -zaa -23a 6 I 23 6a 23/ -23 48 g a 23? 8 23 236 V 8 23c 307a 5 20 23 I 1 20a 7 mmmnl' 24d 7 ,1 20b 7 I iii Inventors Wallace 15.Watson 'Arch ur- D. Wilson,

by flax; B M

Their" Attorney Patented Mar. 31, 1953 STATES PATENT OFFICE ADJUSTABLEGEARING DEVICE Wallace'B; Watson, Clay, and Arthur D. Wilson, CentralSquare, N.. Y., assignors: to. General: Electric CompanmacorporationoiiNew York- Application Feb'ruary 14, 1951, Serial N'.-210','938' 5Claims. (Cl. 74-344) This? inventionrelatest to: devices? fortransmitting; mechanical power: between rotating... shafts; and more;particularly to; devices: capable: of: ad. justmentatorprovide aplurality'ofmputto output shaft:- SDI-38112171051.

In:the-field.ofrmeasuringinstruments, partied-- larly of the visualindicating'type where: adisplay is; presented along: a.- given base"1ine,-.it.isoften desirabletoiemployrazcalibratedmarker'or pointer. toread ofl; the; measured data; Forexample,.,in. the case: of: radar?typ'el obstacle detection where thecdetect'edi objects are. displayed inspaced positionzalon'gv a: given: time; base; in accordance with the:rangezoflthe. respectiveobjects. from areference position}, anelectronic marker signal is generated andits'. position along the timebase is. manually controlled by the' operator. The manual control is;calibrated with great accuracy, thereby permitting; a. precise:measurement when the control is adjusted. to obtain coincidence'ofthee-marker. and the indication corresponding to theidetected object.One such control comprises manual rotation of. a shaft which controlsthe position oftthe-marker along'the time-base. Therotationof. the.shaft. is. calibrated to read the rangeof'thedetected object,thecalibration ordinarily beingin yardsfor short ranges, for. exam pleup to fifty miles, and miles for longer ranges.

However, operational1y,.it is desirable that the marker indication moveslowly along the. time base'forshort ranges of'the' detectedobjects-and. then" move more rapidly along, the time base for thelongeriranges of the detected'obj'ectl Aineed thus exists for acontroldevice which, with relatively the same input shaft speed ofrotation, will"'produce" one" output shaft speed for close rangesandahigheroutput shaft speed for the more distant ranges: Of course;toruleout human error, such a-device should be foolproof inthattheoutputtoinput speed'or gear ratio should not be" left to thediscretion of the operator; Rather; thedevice should" in'cludemechanicalinterlocking so that from the zero position to a certain: range, for"example fifty miles; only one gear ratio" can be used" while above thatrange only *the=o'ther gear ratio" can be used until the limit of thesystem is" reached Ifi is" an ob'ject of thisinvention; therefore,- toprovide an adjustable gearing device which" is rotatable for." as-predet'ermined 1 number of revolutionsbetween a'zeroi position andalimit position, and which: adjustment of" the gears can" be made $1 onlyone point in -the travel between the zero: andilimit' positions-s is a=morespecific object of this invention other? gear: ratio may be:employed between the adjusting point andthe limitposition.

Inanradjustablei gearing device. embodying this invention, there: is.provided.v a manually operable inputshaft which .isLrotatablymountedand!v ally: movable to apair. of. predetermined positions: Mountedonxits input. shaft? are a cam. disc? which is provided with a recess, asingle-tooth gear, a plurality ofoutput spur: gears; and a signallingspur gear. Disposed to be. driven by the output spurgears are aplurality ofiactuated' spur gears which are mounted on a rotatableoutput shaft; Each of the actuated spur gears: engages a; different one.of. the output spur gears depending upon the axial position of theinput. shaft to provide: different speed ratios (between the input andoutput shafts;

Also disposed to be driven by theLinputt'shaft a rotatable signallingum't'; Included in this signalling unitin fixed angular" relationship toeach other are? an actuating spur gear; a p'airrof double-to'othg'ears',and a cam disc: The actuatin'gspur gear'is arranged to engage thesignalling spur gear: at both axial positions ofthe input shaft; whilethe doub1e-tooth gears are each di'sposed to coa'ct' with thesingle-tooth gear at a different'one of the axialp'ositions of the inputshaft: Means are thereby provided which limit the number of'revolutionthat the input shaft may makein' either of its axial positions. Moreover; the angular'positions' of the double-tooth gearswith respect toeachother are correlated so" that oneof thei limits placed ontherota'tion of the input shaft either of its'vaxia'l positions occurs atthe same angular position of the input shaft with respect to thesignalling unit;.th is midstop po'sition being reached in one axialposition of the shaft by'rotation in onedirection and being reached'intheoth'er axial'position of the shaft by" rotation in the otherdirection. Thus, the travel in either axial'shaft position does not.overlap the travel'in the other position; The cam-disc of the signallingunit is arranged to coactwith' the recessed cam disc on the input shaft"to permit displacement of the input shaft between its axialposi'tionsatthe above mentioned midstop position of" the signalling unit withrespect to the input shaft? and only at that shaft position.

Thus; to go from'the zero positionor the device to -the-limit position,or Vice'yersa; one axiafposi tion of the input shaft is employed to gofrom the zero position to the midstop or adjusting position, the otheraxial position must be employed to go from the adjusting position to thelimit position. Since the gearing between the input and output shafts isdependent upon the axial position of the input shaft, the desired resultof two different output to input shaft speed ratios is thereby attained.

For a better and more complete knowledge of my invention, together withadditional objects and advantages thereof, reference should now be hadto the following description and accompanying drawing in which:

Fig. 1 is a longitudinal view in section of an adjustable gearing deviceembodying this invention, the device being shown in the midstop oradjusting position with the input shaft displaced to one of its axialpositions;

Fig. 2 is a longitudinal view of the device of Fig. 1, also showing thedevice in the adjusting position but with the input shaft displaced toits other axial position;

Fig. 3 is a diagrammatic sketch showing the singleand double-tooth gearmeans used to limit the travel of the device, as well as the cam meansused to prevent displacement of the input shaft except at the adjustingpoint, the illustrated angular and axial positions of the cam and gearmeans being that which occurs when the input shaft is in the positionshown in Fig. 1; Fig. 4 is another diagrammatic sketch of the gear andcam means shown in Fig. 3 illustrating their positions when the inputshaft is in the position shown in Fig. 2; and

Fig. 5 is still another diagrammatic sketch of the gear and cam meansshowing them in the limit position.

Referring to Fig. 1, in a preferred embodiment of our invention, a shaftI is journaled for rotation in a stationary bearing member 2 and arotatable bearing member 3. Means for rotating shaft I is provided by ahandwheel 4, on which a knob 5 is mounted for ease of operation.

Secured to shaft I so as to be rotatable therewith are gear members 6and I, and formed as an integral part of the shaft is a spur gear 8.Member 6 includes a single-tooth gear 6a, and a cam disc 6b, which isprovided with a circular segmental recess, i. e., flatted on one side;and member 1 includes two output spur gears Ia and 1b of differentdiameters and conventional design. Cut in the larger diameter gear 1b isan aperture through which there extends a pin 9. Pin 9 is secured to anannular member II), which in turn is mounted on bearing member 3. Alsomounted on bearing member 3 are a washer II and a coupling I2 for aflexible output shaft I3. Shaft I3 thus turns when bearing member 3rotates in the stationary bearing member I4, in which it is journaledfor rotation.

Shaft I is not only mounted rotatably, but it also may be displacedaxially within certain limits, member I striking member I to provide astop in one direction and a positioning washer I secured to shaft Istriking the frame I6 of the device to provide the stop in the otherdirection. Bearing 3 and the various members secured to it, however, arenot axially movable.

The various gear members mounted on shaft I are arranged to cooperatewith gear members which are mounted on an adjacent shaft I'I. Shaft I1is journaled for rotation in stationary bearings I8 and I9 and is notmovable axially.

Secured directly on shaft I1 is a gear member 20. while disposed aroundshaft I! but rotatable with respect to it on bearing members 2I and 22is a signalling unit or gear member 23. Gear member 20 includes spurgears 20a and 20b. which respectively engage gears Ia and lb, dependingupon the axial position of shaft I, and gear member 23 includes anactuating spur gear 23a, double-tooth gears 23b and 230, and cam disc23d. As is shown in Fig. 3, and as will be more fully describedhereinafter, the teeth 23c and 23f of gear 231), and the teeth 23g and2311. of gear 230, cooperate with the single tooth of gear Go forsignalling the angularposition of shaft I! with respect to shaft I,while cam disc 23d together with cam disc 61) prevents axial movement ofshaft I except at one predetermined angular position of cam 6b withrespect to cam 23d. For that purpose, cam disc 23d may be provided witha circular segmental recess.

As previously mentioned, shaft I1 is not movable axially. In order toprevent axial movement of shaft I! in one direction a positioning member24 and a washer 25 are mounted on the shaft, while the coupling 26 bywhich the output shaft 21 is linked to shaft II prevents movement in theother direction.

In operation, shaft I is both rotated and moved axially, when suchmovement is possible, by means of handwheel 4. The axial movement ispossible only when the cams 6b and 23d. are in the position shown inFigs. 1, 2, 3, and 4. Figs. 1 and 3 illustrate shaft I displaced to theaxial position where gear Ia meshes with gear 20a. for one output speedratio between shafts I and I1, While Figs. 2 and 4 illustrate the shaftdisplaced to its other position where gear 'Ib meshes with gear 20b toprovide the other output speed ratio.

In either case, shaft II turns in the opposite direction of rotation toshaft I.

Viewing the device from the handwheel end, if the device is in theposition of Fig. 1, shaft I can be rotated only in the counterclockwisedirection. This is due to the fact that if it is attempted to rotateshaft I in the clockwise direction, gears 6a and 8 attempt to rotatemember 23 at different speeds, which results in locking of the device.Specifically, the single tooth of gear 6a meshes with tooth 23o of gear23b to drive member 23 at one speed, while gear 8 meshes with gear 23ato drive it at another speed. Of course, this prevents any movement atall of member 23 and thus of shafts I and I1.

However, if the handwheel is turned in the counterclockwise direction,there is no interference since the single tooth of gear 6a moves awayfrom tooth 236, as gear 6a is turned more rapidly by shaft I than member23 is turned by gear 8. By the time gear 6a has made one revolution,gear 231) has turned sufiiciently that the tooth of gear So does notcontact tooth 23c, and additional rotation of shaft I and thus of shaftI! may continue. However, after a number of revolutions, in this case 5revolutions of the input shaft, gear 232) has rotated sufficiently thatthe tooth of gear 60. contacts tooth 23f. This locks the device due tothe same type of interaction as described above and prevents furtherrotation of either shaft. Thus, with shafts I and H in the positionsshown in Fig. l, 5 revolutions of shaft I may be made in thecounterclockwise direction and rotation in the clockwise direction isimpossible. The output speed of shaft I1, and thus of shaft 21,throughout Rotation of-shaft I in' the clockwise direction.

from the position;- of Fig. 1" may be obtained.

however: -by displacinggshaft l: axially: tothey position show-m in"Fig: 2 E- possible: since thewfiats on camdiscs:- lib and-23d-I'arejuxta is" displaced j gears 8: and 23m: still-,re

maiminengagementi Rotation in" the" clockwise:

directions may then be accomplished and cone ti'nued until gear: 23crotates suffici'entl-yr for;

tooth 2.311%- and" the, single tooth of it gear 6m to come? intocontactt In-the--illustrated device;

output: specifiof? shaft 1T.- being' dependent; upon thearatio: ofgthe:diameters of the, gears l li andv and"-tootht 237i: result'sjn thesame'typeof -'locking as described" above; This: locking; is illustratedin .Eigafijgwhibh. alsoshowshowcams 6b and 23d coactfltio; prevent"axial disp a nt f s a t l except" at the one desired adjusting position.

been made, and handwheel 4 then turned for 5 turns so that tooth 23 andthe single tooth of gear 6a have come into contact to prevent furthercounterclockwise rotation, shafts I and I! are then in the zero rangeposition, when, for example, the device is used to control a rangemarker. Now, as the handwheel is turned in the clockwise direction, therange marker as driven by shaft 21 moves outwardly at a certain rate ofspeed, depending upon the gearing between shafts l and I1. After acertain predetermined distance of travel of the range marker at thisfirst rate, 1. e., 5 turns of handwheel 4, single-tooth gear 6a engagestooth 23a of gear 23b, stopping movement of the range marker andsignalling that the gear should be shifted, i. e., shaft I displaced tothe position shown in Fig. 2, for more efficient operation of the rangemarker. Once this is done, the range marker again may be movedoutwardly, but now at a different rate of travel, until gear 60!.contacts tooth 23h of gear 230 after four turns of handwheel 4. Thissignals that the range marker has been moved to the limit of the system.

The different rates of travel of the range marker thus provide differentaccuracies of the system at different ranges. Thus, from the zeroposition up to a certain specified range, for example 50 miles, thegearing between shafts l and I1 provides a certain accuracy, i. e.,distance moved by range marker per revolution of handwheel 4, whileabove that range the new gearing between the shafts provides a differentaccuracy. However, above the specified range, the necessity forincreased speed of operation outweighs the accuracy factor. In fact, aprimary purpose of the gear shifting device is to provide means formeeting this need for increased speed of operation and an importantadvantage of the device is that it includes means which require thecorrect speed to be used in each range.

The device illustrated in the drawmg 1s 1ntended to be merelyillustrative. By different permitting" movement; of -shaft. I i. As.

6a spacingaof the teeth; of? the double-tooth. geaasiwellas=bydifferentarrangementofvtheigears; and the-cam discs, the;device could? be, made operable over' shorten or" longer ranges: M'oreover,- member -23 coul'd be mounted on a=separater shaft'rather thanonshaft l1, if it were so dew sired. Thus; while there have beendescribed; what at present 'is consideredto be= the preferred embodimentof this invention, it will be obvious? to thoseskilled in. the-art thatvarious' alterations and modificationsmay" be made therein without"departing from the invention, and it'- i's; therefore; aimed -intheappended" claims to cover all such changes and modifications as failwithin the; true spiritandiscope' of the-inventions What" we; claimasnewand, desire: to- -secure' by- Batters- Patent of the: United"States-is:-

1: In" an"; adjustable gearing" device for: trans? mitting mechanical"power, a, rotatable inputshaft'" axia'lly movable to a pair ofpredetermined positions, having mounted thereon a cam disc providedwith' a recess; a single-tooth. gear: a" plurality of output spur gears;and a; driving gear; a rotatable output shaft having; mounted, thereon aplurality ofspur -gears-each' forengaging a different one of said outputspur gears to provide different speed ratios between said input andoutput shafts depending upon the axial position of said input shaft; arotatable gear unit including in fixed angular relationship to eachother a driven gear arranged to be driven by said driving gear, a pairof double-tooth gears each disposed to coact with said singletooth gearat a different one of said axial positions of said input shaft toprovide means for limiting the number of revolutions of said shafts ineither of said positions, and a cam disc arranged to coact with saidinput shaft cam disc to permit displacement of said input shaft from oneof said axial positions to the other of said axial positions at only oneangular position of said gear unit with respect to said input shaft.

'2. In an adjustable gearing device for transmitting mechanical power, arotatable input shaft axially movable to a pair of predeterminedpositions having mounted thereon a cam disc provided with a circularsegmental recess, a singletooth gear, a plurality of output spur gears,and a driving gear; a rotatable output shaft having mounted thereon aplurality of spur gears, each for engaging a different one of saidoutput spur gears to provide different speed ratios between said inputand output shafts depending upon the axial position of said input shaft;a gear unit disposed in coaxial and rotatable relation with respect tosaid output shaft and including in fixed angular relationship to eachother a driven gear arranged to be driven by said driving spur gear, apair of double-tooth gears each arranged to coact with said single-toothgear at a different one of said axial positions of said input shaft toprovide means for limiting the number of revolutions of said shaft ineither of said positions, and a cam disc provided with a circularsegmental recess and arranged to coact with said input shaft cam disc topermit displacement of said input shaft from one of said axial positionsto the other of said axial positions at only one angular position ofsaid gear unit with respect to said input shaft.

3. In combination with a pair of rotatable shafts, means coupled to eachof said shafts for providing a mechanical connection therebetween andincluding a pair of portions displaceable rela tive to one anotherbetween first and second operating positions, each of said positionsdetermining an individual transmission ratio between said shafts, meansresponsive to the rotational position of one of said shafts forpreventing relative displacement of said portions for any rotationalposition of said one shaft exclusive of a reference position, and stopmeans for limiting rotational movement of said one shaft to apredetermined number of revolutions in each direction from saidreference position.

4. In combination, a first rotatable shaft, a second axially movable,rotatable shaft, means coupled to each of said shafts for providing amechanical connection therebetween and including a pair of portionsdisplaceable relative to one another with axial movement of said secondshaft between first and second operating positions, each of saidpositions determining an individual transmission ratio between saidshafts, means responslve to the rotational position of said second shaftfor preventing axial displacement thereof for any rotational position ofsaid second shaft exclusive of a reference position, and stop means forlimiting rotational movement of said one shaft to a predetermined numberof revolutions in each direction from said reference position.

' 5. In combination with a pair of rotatable shafts, means coupled toeach of said shafts for providing a mechanical connection therebetweenand including a pair of portions displaceable relative to one anotherbetween first and second operating positions, each of said positionsdetermining an individual transmission ratio between said shafts, meansresponsive to the rotational position of one of said shafts forpreventing relative displacement of said portions for any rotationalposition of said one shaft exclusive of a reference position, and stopmeans responsive to the positioning of said portion for limitingrotational movement of said one shaft between said reference positionand a predetermined number of revolutions in one direction for saidfirst operating position of said portions and for limiting rotationalmovement of saidone shaft between said reference position and apredetermined number of revolutions in the opposite direction for saidsecond operating position of said portions.

WALLACE B. WATSON. ARTHUR D. WILSON.

No references cited.

